Process for the deodorization of omicron, omicron-dimethyl-dithio-phosphate of diethyl mercapto-succinate



2,844,619 Patented July 22, 1958 hypochlorite and extending saidstirring operation over a 2,34463319 period of 30 minutes at atemperature not in excess of 50 C. and thereafter allowing same to cooloff to room PRGCESS FUR THE DEGDORIZATION F 0,0-

Y W temperature. QEQ a F ZZgiQ 0F DIETHYL 5 At this stage, thehypochlorite is removed from the lWRLAPIfi'SJ (cmk solution bysubmitting the liquid mass to the action of a duan Nebrera lEscobar,Madrid, Spain a uum filter, or by decantation.

The resultant product is then finished and ready to be N0 Amhmtmn June1955 mixed with inert vehicles, or to be dissolved in water in 5mm513571 10 compliance with a conventional formula. Claims priority,application Spain April 12, 1955 Hereinafter, the process to whichreference is made in the present specification, will be disclosed bymeans of 1 Claim (CL 269-461) a non-limiting example.

In an appropriate mixer having an enameled or vitrified The presentinvention relates to a process for the debottom and provided withcooling means, there are placed odorization of0,0-dimethyl-dithio-phosphate of diethyl 100 parts of0,0-dimethyl-dithio-phosphate of diethyl mercapto-succinate, utilizingto this effect an energetic mercapto-succinate, and while this productis being stirred, oxidizing agent. 50 parts of an aqueous solution ofsodium hypochlorite The product termed 0,0-dimethyl-dithio-phosphate ofcontaining 47 to 50 parts by volume of hypochlorite per diethylmercapto-succinate possesses extraordinarily acthousand parts by volumeof solution are added grad tive properties applicable for destroyinginsects; however, ually, taking care that the temperature does notexceed it is likewise noted for its intense sulfurous emanations 50 C.,and thereafter this stirring operation is extended of a most loathsomesmell, for which reason its applicaover a period of 30 minutes, allowingthe liquid mass to tion as an active insecticide has been restricted toa cercool ofi to room temperature. tain extent, that is to say, for thedestruction of agricul- The mixer should be provided with a bell-shapedfunnel tural pests in open spaces. capable of collecting, by suctionmeans, all such gases With the object of also making use of the activeprinthat are produced during this reaction and to conduct ciple of0,0-dimethyl-dithio-phosphate of diethyl merthese to the open airoutside the building. capto succinate in the preparation of insecticidesfor use Thereafter the liquid mass is poured into a settling tank inclosed spaces, as for example, domestic insecticides, so as to separatethe 0,0-dimethyl-dithio-phosphate of divers studies and experiments havebeen made which diethyl rnercapto-succinate from the hypochloritesoluhave eventually led to the process claimed by the present tion and,when this is divided into two distinct layers, of

invention and by means of which 0,0-dimethyl-dithiowhich the upper isconstituted by the hypochlorite soluphosphate of diethylmercapto-succinate is deprived of tion and the lower by the0,0-dimethyl-dithio-phosphate its oifensive smell, without loss oraffecting any of its of diethyl mercapto-succinate, these are thenseparated original active properties applicable for the destruction ofby the action of vacuum filtration, or by decantation.

i t After having separated the active matter, this is then Uponinitiating research work for the production of a filtered.

deodorant for 0,0-dirnethyl-dithio-phosphate of diethyl WhatI claim is:

mercapto-succinate, destitute of all detrimental action Aprocess for thedeodorization of 0,0-dimethyl-dithiowith respect to its insecticidepotential, it was taken into phosphate of diethyl mercapto-succinate,which consists account that said product is very sensitive to water andessentially in the gradual addition to the said 0,0-dimoisture, so thatupon establishing contact with other methyl-dithio-phosphate of diethylmercapto-succinate,

bodies whose degree of moisture exceeds 2%, it will hywith stirring, ofan aqueous sodium hypochlorite solution drolyze and thereby graduallylose its active properties. containing 47 to 50 parts by volume ofhypochlorite per The oxidizing capacity of chlorine was first taken intothousand parts by volume of solution, 50 parts by volume consideration,due to its great affinity with hydrogen and of the said solution beingadded for each 100 parts by by virtue of which it will remove thehydrogen from all volume of 0,0-dimethyl-dithio-phosphate of diethylorganic substances, decomposing same, or else produce amercapto-succinate, continuing the stirring for about 30 decompositionof any water present by liberating the 50 minutes after completion ofsuch addition, thereafter oxygen that will oxidize said organicsubstances. Howallowing the mixture to cool to room temperature, and

ever, although free available chlorine can only be applied separatingthe deodorized product from the hypochlorite with ditficulty, thiselement offers certain alternatives, solution.

i. e. those of the hypoohlorites, that are very active oxidizing agents,with the advantage that the hypochlorous acid References Cited in thefile of this Pawnt of the hypochlorite can easily be freed by weakeracids, UNITED STATES PATENTS such as carbonic acid gas (car-hon dioxide)from the atmosphere. It was thus found that any of the hypo- 119311058Clemmensen 33 chlorites can readily be applied as a deodorant for 0,0-2,578,652 Cassaday 51 dimethyl-dithio-phosphate of diethylmercapto-succinate, 50 217131018 Johnson ly 955 thou h the best resultshave been obtained with sodium hypogchloflte OTHER REFERENCES Thepresent process consists in submitting 0,0-dimethyl Gregory: Uses andApplications of Chemicals and dithio-phosphate of diethylmercapto-succinate to the Related Materials, vol. I (1939), and vol. 11(1944), oxidizing action of a hypochlorite solution, preferably of pages5423, and 301, respectively, Reinhold Pub. Corp., sodium hypochlorite,which is achieved by stirring 0,0- New York.

dimethyl-dithio-phosphate of diethyl mercapto-su'ccinate U. S. Dept. ofAgriculture, Pub. E832, December 1951, in an appropriate container whilegradually adding thereto 4 pages.

